Ferrous Ion Chelating Activity Research Articles

Determination of nutritional composition, enzyme inhibitory activity and antioxidant activity of pretreated, dehydrated <em style="mso-bidi-font-style: normal;">Amaranthus viridis</em> L. Leaves

Amaranthus viridis L., belongs to the family Amaranthaceae is a perennial edible plant, and traditionally used for medicinal treatments in South Asia. Despite the significant uses of the plant, availability of scientific data on plant's biological efficiency is lacking in the scientific domain. There is a higher potential and demand for dehydrated value-added products from the local and international market. Hence, the objective of the research was to determine the impact of pretreatments and dehydration on nutritional composition, phytochemical profile, antioxidant activity, and enzyme inhibitory activity of A.viridis leaves. Magnesium oxide 0.1% (w/v), sodium bicarbonate 0.1% (w/v) and potassium metabisulphite 0.5% (w/v) were selected as the best pretreatment based on the experiments. The pretreated leaves were steam blanched (5 min), followed by dehydration at 60 ± 1°C for 12 hours. Protein (21.90 ± 1.01%db), fat (3.70 ± 0.02%db), fiber (5.90 ± 0.05%db), ash (11.30 ± 0.12%db) and carbohydrate (49.24 ± 0.08%db) were determined. Data was statistically analyzed using one-way analysis of variance (ANOVA) test at a 95% confidence level (p < 0.05). A qualitative phytochemical analysis was conducted. The total phenolic content, 5.89 ± 0.30 mg in Gallic acid equivalents per 1g was determined in pretreated, dehydrated powder. FRAP, DPPH radical scavenging activity and ferrous ion chelating activity of the methanolic extract were 20.22 ± 0.45 mg Trolox equivalents, 1.68 ± 0.07 mg in Trolox equivalents and 3.83 ± 0.06 mg EDTA equivalents per 1g of pretreated dehydrated leaf powder, respectively. Methanolic extract (500 μg/mL) showed inhibitory activity of 25.30 ± 0.60% on 5-lipoxygenase, 30.80 ± 0.50% on alpha-amylase and 25.60 ± 0.40% on alpha-glucosidase. Inhibitory activity was not detected against lipase, acetylcholine esterase and butyrylcholinesterase enzymes. In conclusion, pretreated, dehydrated, A. viridis leaves are recommended as a health beneficial food ingredient.

Structure, physicochemical properties, and biological activities of protein hydrolysates from Zanthoxylum seed.

Zanthoxylum seed, as a low-cost and easily accessible plant protein resource, has good potential in the food industry. But protein and its hydrolysates from Zanthoxylum seed are underutilized due to the dearth of studies on them. This study aimed to investigate the structure and physicochemical and biological activities of Zanthoxylum seed protein (ZSP) hydrolysates prepared using Protamex®, Alcalase®, Neutrase®, trypsin, or pepsin. Hydrolysis using each of the five enzymes diminished average particle size and molecular weight of ZSP but increased random coil content. ZSP hydrolysate prepared using pepsin had the highest degree of hydrolysis (24.07%) and the smallest molecular weight (<13 kDa) and average particle size (129.80 nm) with the highest solubility (98.9%). In contrast, ZSP hydrolysate prepared using Alcalase had the highest surface hydrophobicity and foaming capacity (88.89%), as well as the lowest foam stability (45.00%). Moreover, ZSP hydrolysate prepared using Alcalase exhibited the best hydroxyl-radical scavenging (half maximal inhibitory concentration (IC50 ) 1.94 mg mL-1 ) and ferrous-ion chelating (IC50 0.61 mg mL-1 ) activities. Additionally, ZSP hydrolysate prepared using pepsin displayed the highest angiotensin-converting enzyme inhibition activity (IC50 0.54 mg mL-1 ). These data showed that enzyme hydrolysis improved the physicochemical properties of ZSP, and enzymatic hydrolysates of ZSP exhibited significant biological activity. These results provided validation for application of ZSP enzymatic hydrolysates as antioxidants and antihypertensive agents in the food or medicinal industries. © 2023 Society of Chemical Industry.

Effects of spices mixture and cooking on phytochemical content in Ethiopian spicy hot red pepper products

AbstractSpicy hot red pepper, the most popular spice in Ethiopia, is also locally known as berbere, which is highly valued for its pungency, flavor, and color. The spicy hot red pepper powder is used to flavor shiro and other stews, as well as different forms of condiments. The aim of this study was to measure the phytochemical content of raw spices (black cumin, garlic, ginger, and cardamom) and control hot red pepper (HRP), as well as the raw and cooked experimental and commercial spicy hot red pepper products. The samples were analyzed for phytochemical content using a spectrophotometer. Compared to raw experimental spicy hot red pepper, raw spices, and HRP, raw commercial spicy hot red pepper exhibited the highest bioactive phytochemicals. The cooked commercial spicy hot red pepper or sauté had the highest total flavonoid content (TFC) and total carotenoid content (TCC). Similarly, cooked experimental spicy hot red pepper contained the highest levels of total phenolic content (TPC) and β‐carotene. With r values ranging from 0.24 to 0.65, the TPC and TFC of raw spices were correlated with antioxidant activity. There was a significant correlation between TCC and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) (r = .71), 2, 2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) (r = .95), and ferric ion reducing antioxidant power (FRAP) (r = .76), as well as between β‐carotene and DPPH (r = .69), FRAP (r = .69), and ferrous ion chelating activity (FICA) (r = .78). This study verified that raw spices and their mix with hot red pepper are good sources of bioactive phytochemicals with radicals scavenging abilities in Ethiopian diets.

Influences of Yogurt with Functional Ingredients from Various Sources That Help Treat Leaky Gut on Intestinal Barrier Dysfunction in Caco-2 Cells.

The impact of yogurts made with starter culture bacteria (L. bulgaricus and S. thermophilus) and supplemented with ingredients (maitake mushrooms, quercetin, L-glutamine, slippery elm bark, licorice root, N-acetyl-D-glucosamine, zinc orotate, and marshmallow root) that can help treat leaky gut were investigated using the Caco-2 cell monolayer as a measure of intestinal barrier dysfunction. Milk from the same source was equally dispersed into nine pails, and the eight ingredients were randomly allocated to the eight pails. The control had no ingredients. The Caco-2 cells were treated with isoflavone genistein (negative control) and growth media (positive control). Inflammation was stimulated using an inflammatory cocktail of cytokines (interferon-γ, tumor necrosis factor-α, and interleukin-1β) and lipopolysaccharide. The yogurt without ingredients (control yogurt) was compared to the yogurt treatments (yogurts with ingredients) that help treat leaky gut. Transepithelial electrical resistance (TEER) and paracellular permeability were measured to evaluate the integrity of the Caco-2 monolayer. Transmission electron microscopy (TEM), immunofluorescence microscopy (IM), and real-time quantitative polymerase chain reaction (RTQPCR) were applied to measure the integrity of tight junction proteins. The yogurts were subjected to gastric and intestinal digestion, and TEER was recorded. Ferrous ion chelating activity, ferric reducing potential, and DPPH radical scavenging were also examined to determine the yogurts' antioxidant capacity. Yogurt with quercetin and marshmallow root improved the antioxidant activity and TEER and had the lowest permeability in fluorescein isothiocyanate (FITC)-dextran and Lucifer yellow flux among the yogurt samples. TEM, IM, and RTQPCR revealed that yogurt enhanced tight junction proteins' localization and gene expression. Intestinal digestion of the yogurt negatively impacted inflammation-induced Caco-2 barrier dysfunction, while yogurt with quercetin, marshmallow root, maitake mushroom, and licorice root had the highest TEER values compared to the control yogurt. Yogurt fortification with quercetin, marshmallow root, maitake mushroom, and licorice root may improve functionality when dealing with intestinal barrier dysfunction.

Effect of phosphorus fertilization on phenolic compounds and antioxidant activity in Galanthus elwesii Hook.

Snowdrop is a genus of high medicinal value with alkaloids such as galantamine, and lycorine of the Amaryllidaceae family. The present study was conducted to have an effect on the effects of phosphorus (P) treatment on antioxidant activity and phenolic compounds in Galanthus elwesii Hook. The plants were exposed to different concentrations of P ( 0, 3, 6, and 12 kg da-1). The study was carried out in the 2018-2019 growing season. G. elwesii were harvested based on different growing stages (flowering and fruit ripening). In this study, the bulb and roots of the plant were used. Total flavonoid content (TFC), total phenolic content (TPC), phenolic compounds, and antioxidant activity were determined in harvested bulb and roots. The highest TPC was detected as 358.36 mg GAE/g in the flowering period of the plant, and the lowest TPC determined as 80.13 mg GAE/g in the fruit ripening period in the treatment P 6 kg da-1. The highest TFC was detected as 108.07 mg QE/g with the flowering period of the plant, and the lowest TFC was determined as 52.33 mg QE/g in the fruit ripening period in the treatment P 6 kg da-1. The main phenolic component of G. elwesii was determined to be gallic acid (GA). In antioxidant activity, while the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity (72.30%) was in the flowering period in the treatment P 6 kg da-1, the highest ferrous ions chelating activity (66.77%) was detected in the fruit ripening period in the treatment P 6 kg da-1. As a result, it was determined that TPC, TFC and DPPH activity in G. elwesii of flowering period ˃fruit ripening period.

Investigating the Microwave-Assisted Extraction Conditions and Antioxidative and Anti-Inflammatory Capacities of Symphytum officinale WL Leaves

Symphytum officinale (comfrey) is a perennial herb native to West Asia and Europe. Its root extracts are commonly used as a natural remedy to treat muscle, joint, skin, and bone disorders, especially in Europe. However, more information is needed on the biomedical functions of comfrey leaves. This study’s sequencing results of internal transcribed spacer and trnL–trnF genes showed that plants purchased from the local market were comfrey and named S. officinale WL (WL). The suitable extraction conditions of the WL leaves with the highest extract yield and total phenols and flavonoid contents by microwave-assisted extraction were identified. The antioxidative and anti-inflammatory activities and possible molecular mechanism(s) of the WL leaf extract (WLE) were evaluated. Furthermore, the major component of WLE was identified as rosmarinic acid by HPLC. Results showed that the optimal extract condition was obtained with 750 W microwave power, 50 °C, 75% methanol, the solid-to-solvent ratio of 1:10, and 15 min. Results of all DPPH, ABTS, and superoxide radical scavenging activities, reducing power, ferrous ion chelating activity, and ferric reducing antioxidant power showed high antioxidative capacities of WLE. Furthermore, WLE showed prominent DNA-protecting activity. WLE attenuated lipopolysaccharide-stimulated inflammation by suppressing iNOS, COX-2, IL-1β, IL-6, and TNF-α expressions in the RAW264.7 macrophages. These attenuations are involved in the inactivation of lipopolysaccharide-stimulated NF-κB and MAPK signaling pathways. Therefore, the comfrey leaf extract obtained via a time- and energy-saving microwave-assisted extraction may be a potential antioxidative and anti-inflammatory biomedicinal agent.

Identification and evaluation of antioxidant peptides from highland barley distiller's grains protein hydrolysate assisted by molecular docking

The aim of this study was to identify antioxidant peptides from highland barley distiller's grains and evaluate their antioxidant activity in vitro. The results showed that the enzymatic hydrolysate of highland barley distiller's grains prepared by ultrasonic assisted alkaline protease had antioxidant properties, aromatic amino acids accounted for 61.48% of the total free amino acids and acidic/basic amino acids accounted for 40.82% of the total hydrolyzed amino acids in enzymatic hydrolysate. Ultrafiltration component F1 (Mw < 1 kDa) had the highest DPPH, ABTS and hydroxyl radical scavenging activity and ferrous ion chelating activity, which were 93.92%, 69.59%, 50.27% and 0.71, respectively. Four peptides were identified and screened by LC-MS/MS and the P1 (SWDNFFR) and P4 (WDWVGGR) showed high scavenging ability of DPPH free radical (70.23%-62.84%) and ABTS free radical (30.87%-60.54%). Molecular docking showed that P1 and P4 formed multiple hydrogen bonds with central residues of MPO.

Emerging Insights into the Applicability of Essential Oils in the Management of Acne Vulgaris.

The occurrence of pustules, comedones, nodules, and cysts defines acne vulgaris, a prevalent chronic inflammatory dermatological condition. In the past few decades, essential oils extracted from varied natural sources have acquired recognition due to their potential medicinal applications in acne therapy. However, there is not yet sufficient medical data to fully characterize this interaction. Multiple factors contribute to the development of acne vulgaris, including excessive sebaceous production, inflammatory processes, hyperkeratinization, and infection with Cutibacterium acnes. Essential oils, including oregano, lavender, lemon grass, myrtle, lemon, thyme, eucalyptus, rosemary, and tea tree, have been found to possess anti-inflammatory, antioxidant, and antimicrobial properties, which may target the multifactorial causes of acne. Analytical methods for determining antioxidant potential (i.e., total phenolic content, diphenyl-1-picrylhydrazyl free radical scavenging assay, reducing power assay, ferrous ion chelating activity, thiobarbituric acid reactive species assay, β-carotene bleaching assay, etc.) are essential for the evaluation of these essential oils, and their method optimization is crucial. Further studies could include the development of novel acne treatments incorporating essential oils and an assessment of their efficacy in large clinical trials. In addition, further research is necessary to ascertain the mechanisms of action of essential oils and their optimal doses and safety profiles for optimal implementation in the management of acne vulgaris.

Bioactivities of Garcinia kola enzymatic hydrolysates at different enzyme–substrate ratios

Natural products, such as enzymatic hydrolysates and bioactive peptides from dietary sources, are safe alternatives to synthetic compounds linked to various deleterious effects. The purpose of this study is to determine the in vitro bioactivities (antioxidant and anti-inflammatory activities) of Garcinia kola seeds enzymatic hydrolysates (GKPHs) at different enzyme (pepsin)-substrate ratios. G. kola protein, isolated by alkaline solubilization and acid precipitation, was hydrolyzed with pepsin at varying enzyme–substrate (E:S) ratios. The antioxidant parameters investigated include 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging, hydrogen peroxide scavenging and ferrous ion (Fe2+) chelating activities. For anti-inflammatory properties, membrane stabilization and protein denaturation activities tests were used. GKPH produced at 1:32 had the highest degree of hydrolysis (66.27 ± 4.21%). All GKPHs had excellent in vitro anti-inflammatory properties. However, only enzymatic hydrolysates produced at 1:16 (E:S) ratio chelated iron (II) and as well had the highest percentage hemolysis inhibition of 84.45 ± 0.007%, percentage protein denaturation inhibition of 53.36 ± 0.01% at maximum concentration and exhibited highest DPPH scavenging activity (87.24 ± 0.10%). The enzymatic hydrolysates had excellent solubility, emulsifying and foaming properties. It could be deduced from this study that pepsin at a ratio of 1:16 of G. kola protein produced the most effective enzymatic hydrolysates in terms of their antioxidant and anti-inflammatory activities. G. kola pepsin enzymatic hydrolysates, thus, have potential in development as functional foods and as therapeutics pharmaceutical industries in the management of diseases associated with oxidative stress and inflammation owing to their excellent functional, antioxidant and anti-inflammatory properties.

Comparative Studies on Chemical Profile of Red Soko (Celosia Trigyna) and Green Soko (Celosia Argentea)

Chemical profile of leafy vegetables enable researchers to affirm the constituents present in them as well as knowing their possible usefulness for consumption and medicinal applications. Red and green soko were obtained, rinsed in water and cut into smaller pieces, air dried, grounded and sieved to give 40mm mesh size powder. The powdered samples were analyzed for proximate composition and mineral contents using standard methods. The antioxidant properties such as reducing power, ferrous ion chelating activity 2,2- diphenyl-1picrylhydrazyl (DPPH) radical scavenging activity and 2,2-azinobis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) of samples were determined. Red soko had the higher value of crude lipid (2.36 ± 0.06%), ash content (16.45 ±0.15%), protein (17.06 ±0.06%), and dry matter (89.74 ±0.24%) while green soko had higher value of moisture content (10.86±0.33%), crude fibre (13.66±0.20%), carbohydrate (54.81.81±0.21%) and energy value (297.38±0.89 Kcal/100g). Red soko had the higher values of Mg (25.16 ± 0.22 mg/kg), Fe (2.86±0.05 mg/kg), Zn (0.10 ± 0.02 mg/kg), Mn (0.56 ±0.08 mg/kg), and Cu (0.20 ±0.01 mg/kg) while green soko had higher value of Ca (180.16 ±1.00 mg/kg), Na (73.44 ±0.00 mg/kg), K (694.14 ± 0.96 mg/kg), Pb (0.23 ±0.00 mg/kg) and Se (0.20 ±0.03 mg/kg). Green soko had higher value of ferric reducing antioxidant power (0.36±0.04%), Fe2+ Chelating Activity (4.46±0.09%), DPPH radical scavenging activity (11.75±0.74%) and ABTS+ Radical Scavenging Activity (10.18±0.44%) than red soko. The antioxidant properties (TRAP, Fe2+, DPPH and ABTS+) of green soko were higher than red soko. Green soko is richer in antioxidant properties than red soko.

Aflatoxin B1 Detoxification Potentials of Garlic, Ginger, Cardamom, Black Cumin, and Sautéing in Ground Spice Mix Red Pepper Products.

The uses of natural plant origin bioactive compounds are emerging as a promising strategy to detoxify aflatoxin B1 (AFB1). This study aimed to explore the potential of cooking, phytochemicals content, and antioxidant activities derived from garlic, ginger, cardamom, and black cumin to detoxify AFB1 on spice mix red pepper powder (berbere) and sauté. The effectiveness of the samples was analyzed for AFB1 detoxification potential through standard methods for the examination of food and food additives. These major spices showed an AFB1 level below the detection limit. After cooking in hot water for 7 min at 85 ℃, the experimental and commercial spice mix red pepper showed the maximum AFB1 detoxification (62.13% and 65.95%, respectively). Thus, mixing major spices to produce a spice mix red pepper powder had a positive effect on AFB1 detoxification in raw and cooked spice mix red pepper samples. Total phenolic content, total flavonoid content, 2,2-diphenyl-1-picrylhydrazyl, ferric ion reducing antioxidant power, and ferrous ion chelating activity revealed good positive correlation with AFB1 detoxification at p < 0.05. The findings of this study could contribute to mitigation plans of AFB1 in spice-processing enterprises. Further study is required on the mechanism of AFB1 detoxification and safety of the detoxified products.

LC-ESI-QTOF-MS2 Characterization of Phenolic Compounds in Different Lentil (Lens culinaris M.) Samples and Their Antioxidant Capacity.

Lentil (Lens culinaris M.) is a legume widely consumed worldwide. It is rich in bioactive compounds, including polyphenolic compounds that contribute to positive health benefits. This study aimed to determine the phenolic content and antioxidant activity of black, red, green, and brown whole lentils. Towards this end, the lentils' phenolic compounds were evaluated regarding their total phenolic content (TPC), total flavonoid content (TFC), total tannin content (TTC), total condensed tannin (TCT), total proanthocyanin content (TPAC), total anthocyanin content (TAC). For the antioxidant activity 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), hydroxyl radical scavenging activity (•OH-RSA), ferrous ion chelating activity (FICA), reducing power assay (RPA) and phosphomolybdate (PMA) assay were accessed. To identify individual phenolic compounds, liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS2) was used. The results showed that green lentils exhibited the highest TPC (0.96 mg gallic acid equivalents (GAE)/g) whereas red lentils presented the highest TFC (0.06 mg quercetin equivalents (QE)/g). Black lentils were noted with the highest TCT (0.03 mg catechin equivalents (CE)/g), TPAC (0.009 mg cyanidin chloride equivalents (CCE)/g), and TAC (3.32 mg/100 g) contents. While the greatest TTC (2.05 mg tannic acid equivalents (TAE)/g) was observed in the brown lentil. Regarding the total antioxidant capacity, red lentils (4.01 mg ascorbic acid equivalents (AAE)/g) presented the greatest activity, whereas the lowest was found in the brown samples (2.31 mg AAE/g). The LC-ESI-QTOF-MS2 tentatively identified a total of 22 phenolic compounds, containing 6 phenolic acids, 13 flavonoids, 2 lignans, and 1 other polyphenol. The relationships among phenolic compounds by Venn Diagram showed a high number of overlapping compounds in brown and red lentils (6.7%), and a low number of overlapping compounds between the green, brown, and black lentils (2.6%). Flavonoids were the most abundant phenolic compound within the studied whole lentils, with the brown lentils being the richest in phenolic compounds, especially flavonoids. This study emphasized a comprehensive understanding of the antioxidant potential of lentils and disclosed the phenolic distribution across various lentil samples. This may increase interest in the development of functional food products, nutraceutical ingredients, and pharmaceutical applications with lentils.

Bioactive Compounds, Antioxidant Activity and Sensory Properties of Northern Red Oak (Quercus rubra L., syn. Q. borealis F. Michx) Seeds Affected by Roasting Conditions

The nutritional value and health-promoting properties cause the fruits (acorns) of Quercus spp. to have great potential for use in the food industry as functional ingredients and antioxidants source. The aim of this study was to examine the bioactive compound's composition, antioxidant potential, physicochemical properties and taste characteristics of northern red oak (Quercus rubra L.) seeds subjected to roasting at different temperatures and times. The results indicate that the roasting markedly affects the composition of bioactive components of acorns. In general, the use of roasting temperatures greater than 135 °C causes a decrease in the total phenolic compound content of Q. rubra seeds. Furthermore, along with an increase in temperature and thermal processing time, a remarkable increase in melanoidins, which are the final products of the Maillard reaction, was also observed in processed Q. rubra seeds. Both unroasted and roasted acorn seeds had high DPPH radical scavenging capacity, ferric reducing antioxidant power (FRAP) and ferrous ion chelating activity. Roasting at 135 °C caused negligible changes in total phenolics content and antioxidant activity of Q. rubra seeds. Almost all samples had lower antioxidant capacity along with an increase in the roasting temperatures. Additionally, thermal processing of acorn seeds contributes to the development of the brown color and the reduction of bitterness, and the creation of a more pleasant taste of the final products. Overall, the results of this study show that both unroasted and roasted Q. rubra seeds may be an interesting source of bioactive compounds with high antioxidant activity. Therefore, they can be used as a functional ingredient of beverages or food.

GC-MS Identification of Cholinesterase Inhibitory and Antioxidant Molecules from Leaves of Cnidoscolus aconitifolius (Miller) I.M. Johnston (Euphorbiaceae)

Backgound: Alzheimer’s disease (AD) is a progressive and fatal neurodegenerative disease, clinically characterized by memory and cognitive dysfunction. AD affects about 35 million people worldwide today and is estimated to nearly double every 20 years. Cnidoscolus aconitifolius (Miller) I.M. Johnston has been reported in Nigerian ethnomedicine as a memory enhancer. There is a lack of scientific evidence to justify the claims. Moreover, there are no effective neurotherapeutic agents available for the treatment of AD; hence the need arises to search for new and more effective agents. Objective: This study aims to evaluate and identify potential molecules with anti-Alzheimer’s and antioxidant potentials from Cnidoscolus aconitifolius leaves. Methods: The air-dried leaves of Cnidoscolus aconitifolius (Miller) I.M. Johnston (PCG/UNN/0267) were extracted using the successive extraction procedure based on increasing the polarity of the eluent in the ascending order of n-hexane, ethyl acetate, and methanol. Phytochemical screening was carried out on the extracts using standard procedures. Acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities were done according to Ellman’s method. Eserine was used as standard. Antioxidant potentials were evaluated using standard in vitro chemical analyses. A GC-MS (QP2010SE, SHIDMAZU JAPAN) analysis was done to identify bioactive compounds from the most active fraction. Statistical analyses were performed using one-way ANOVA followed by Dunnett’s Multiple Comparison test at α0.05. Results: Phytochemical analysis revealed the presence of tannins, resins, saponins, flavonoids, phenols, carbohydrates, alkaloids, and terpenoids. Ethyl acetate fraction demonstrated the highest acetylcholinesterase and butyrylcholinesterase inhibitory activity at 1 mg/mL with IC50 values of 0.288 ± 0.00 mg/mL (82.9% inhibition) and 0.440±0.02 mg/mL ((75.4% inhibition), respectively, compared to eserine (IC50=0.050 ± 0.01 mg/mL) for AChE and (IC50=0.049 ± 0.00 mg/mL) for BuChE. Metal (ferrous ion) chelating activity was also high in the ethyl acetate fraction with IC50 value of 0.160 ± 0.00 mg/mL compared to EDTA (IC50 = 0.085 ± 0.00 mg/mL) at 1 mg/mL. Hydroxyl radical scavenging activity was higher in the ethyl acetate fraction (IC50 = 0.352 ± 0.01 mg/mL) when compared to BHT (IC50 = 0.074 ± 0.00 mg/mL) at 1 mg/mL. The pro-anthocyanidin content was also higher in ethyl acetate (6.94 ± 0.16 mg cyanidin/g of sample) compared to other fractions. GC-MS analysis of the most active fraction (ethyl acetate) revealed a total of 56 compounds. The major compounds revealed were: n-Hexadecanoic acid (Area % of 13.45%; Retention time of 14.863), Phytol (Area % of 5.13%; Retention time of 15.864), Octadecanoic acid (Area % of 4.86%; Retention time of 16.211), 9, 12, 15-Octadecatrienoic acid (Z,Z,Z) (Area % of 26.85%; Retention time of 16.09), Squalene (% Area of 2.65%; Retention time of 20.94) and alpha-Tocopheryl acetate (% Area of 1.71%; Retention time of 23.40). Conclusion: C. aconitifolius has the potential to inhibit cholinesterase enzymes involved in the pathology of Alzheimer’s disease. The molecules identified could serve as potential drug leads in managing Alzheimer’s disease.

Chemical Composition, Antioxidant and Antibacterial Activities of Essential Oil Obtained from Chincho (Tagetes elliptica Sm) Leaves Grown in the Peruvian Andes

The chemical composition, antioxidant, and antibacterial properties of the essential oil from the leaves of Tagetes elliptica Sm., grown in Peru, were studied. The EO was extracted using steam distillation, and its chemical composition was analyzed using GC-MS, while the antioxidant activity was evaluated using the radical, scavenging capacity (DPPH and ABTS assays), and ferric reducing antioxidant power (FRAP) assays, ferrous ion chelating (FIC) activity, and the Rancimat test. The antibacterial activity against Staphylococcus aureus, Escherichia coli, and Salmonella infantis was studied using the agar well diffusion method. Twenty-seven compounds were identified in the essential oil, and the major components were cis-tagetenone (37.27%), trans-tagetenone (18.84%), dihydrotagetone (14.38%), and trans-tagetone (5.15%). With regard to antioxidant properties, the IC50 values obtained for the DPPH, ABTS, and FIC assays were 53.37, 46.38, and 22.65 mg/mL, respectively. These values were lower than those obtained for standard butylated hydroxytoluene and ascorbic acid. In the Rancimat test, antioxidant activity was achieved only at high concentration. T. elliptica essential oil showed a marked antibacterial activity against all bacterial strains at all concentrations assayed. This study demonstrated that T. elliptica essential oil could be considered as an alternative to synthetic antioxidants and antimicrobial agents in the food industry.

Phytochemical profile and antioxidant capacity, α-amylase and α-glucosidase inhibitory activities of Oxalis pes-caprae extracts in alloxan-induced diabetic mice

Diabetes and its complications are closely correlated with chronic hyperglycemia, causing severe oxidative stress and leading to glycation reaction with formation of advanced glycation end products. However, medicinal plants are still a source of inspiration for the discovery of new treatments of several diseases, including diabetes. The present study was aimed to evaluate the antioxidant and antidiabetic properties of Oxalis pes-caprae flowers extract in alloxan-induced diabetic mice. The phytochemical and antioxidant activities of both aqueous and methanolic extracts were assessed by in-vitro testing such as free radical scavenging assays (DPPH and ABTS+), ferrous ions (Fe2+) chelating activity and reducing power assay. Additionally, the detection of Amadori products and advanced glycation end products was used to determine the antiglycation potential. α-glucosidase and α-amylase inhibitory assessment was employed to determine the antidiabetic effect, while alloxan-induced diabetic mice were used to measure the in-vivo activities of antioxidants and carbohydrates enzymes. The effect of the methanolic extract on body weight and blood glucose level of extract-treated diabetic mice were also investigated. Among the tested extract, the methanolic extract was the richest in phenolic compounds which is directly related with their remarkable antioxidant, enzyme inhibitory and antiglycation activity. The oral administration of the two doses of Oxalis pes-caprae flowers (150 mg/kg and 250 mg/kg) daily for 3 weeks resulted in hypoglycemic effect compared to the reference drug, glibenclamide (10 mg/kg). Furthermore, the extract was shown to significantly increase the activities of antioxidants and glycolysis enzymes in the liver, kidney and spleen of diabetic mice, compared to diabetic control group. Therefore, Oxalis pes-caprae extract effectively exhibited hypoglycemic and antidiabetic effects as indicated by in-vitro and in-vivo studies, confirming the protective effects on hyperglycemia and oxidative damage.

New C8-substituted caffeine derivatives as promising antioxidants and cytoprotective agents in human erythrocytes

New structurally diverse groups of C8-substituted caffeine derivatives were synthesized and evaluated for their chemical and biological properties. Mass spectrometry, FT-IR, and NMR characterizations of these derivatives were performed. The cytotoxic activity of the derivatives was estimated in vitro using human red blood cells (RBC) and in silico pharmacokinetic studies. The antioxidant capacity of the compounds was analyzed using a ferrous ion chelating activity assay. The ability of the derivatives to protect RBC from oxidative damage, including the oxidation of hemoglobin to methemoglobin, was assessed using a water-soluble 2,2′-azobis(2-methyl-propionamidine) dihydrochloride (AAPH) as a standard inducer of peroxyl radicals. The level of intracellular oxidative stress was assessed using the fluorescent redox probe 2′,7′-dichlorodihydrofluorescein diacetate (DCF-DA). The results indicate that all derivatives are biocompatible compounds with significant antioxidant and cytoprotective potential dependent on their chemical structure. In order to explain the antioxidant and cytoprotective activity of the derivatives, a mechanism of hydrogen atom transfer (HAT), radical adduct formation (RAF), or single electron transfer (SET), as well as the specific interactions of the derivatives with the lipid bilayer of RBC membrane, have been proposed. The results show that selected modifications of the caffeine molecule enhance its antioxidant properties, which expands our knowledge of the structure–activity relationship of caffeine-based cytoprotective compounds.

Chito-oligosaccharides derived from Tilapia Fish Scales; A Powerful Antioxidant

Fish scales are a good source of chitin and collagen that can be used in various cosmetic, biomedical, pharmaceutical, and food industries due to their stability and environmental friendliness. The antioxidant activities of chito-oligosaccharides derived from fish scales evaluated via i) DPPH free radical scavenging activity, ii) superoxide anion radical scavenging activity, iii) ferrous ions chelating activity, and iv) reducing power analysis. The present work results indicated that chito-oligosaccharides (COS) derived from fish scales exhibited good antioxidant activities if compared against other sources of chitosan found in the literature. Thus, the development of bioactive products originated from fish scales could play a remarkable role in the sustainability and biomedical, food, and cosmaceuticals industries.

Synthesis, Characterization, DPPH, Ferric Reducing, and Ferrous Ion- Chelating Activities of Isophthalate Schiff Bases

Aims: The synthesis of bioactive compounds has antioxidant potential. Background: All aerobic bodies including human beings, have antioxidant defense systems that protect them from oxidative damage, and many enzymes to remove or heal damaged molecules. However, this normal antioxidant mechanism can be incompetent, and hence dietary intakes of antioxidant compounds are important. Objective: Synthesis of isophthalate Schiff base derivatives 1-14 and screened for their antioxidant activities (DPPH, ferrous ion Fe2+ chelating and ferric Fe3+ reducing activities) Method: This study aimed to synthesize isophthalate Schiff base derivatives 1-14 and screen them for their antioxidant activities (DPPH, ferrous ion Fe2+ chelating, and ferric Fe3+ reducing activities). Result: Compounds were screened for their antioxidant activities (DPPH, ferrous ion Fe2+ chelating, and ferric Fe3+ reducing activities). Most of the compounds showed significant antioxidant activities. A structure- activity relationship has also been discussed. Conclusion: Most of the synthetic isophthalate Schiff bases were found to be moderately active when screened for their antioxidant activities by three assays such as DPPH radical scavenging, ferrous ionchelating, and ferric reducing activities. These moderately active compounds can serve as lead molecules to further modify the structure and identify more powerful antioxidant agents.

Antioxidant properties, element contents and antimicrobial activities of bee pollen collected by Apis mellifera L. in Türkiye

Aim of study: Recently, pollen has become a preferred nutritional supplement because of its complex composition. We examined the botanical origin, total phenolic/flavonoid content (TPC/TFC), antioxidant/antimicrobial activity, and element content of pollen samples collected from honeybees. This study also examined whether the elements contained in pollen, when consumed as food, posed a risk to human health. Area of study: Ten mixed pollen samples were randomly collected from honeybees in the apiaries of four different Turkish regions, which fall among the three phytogeographic regions of Türkiye. Material and methods: We evaluated total flavonoid (TFC) and phenolic (TPC) contents; antioxidant activities (radical scavenging activity, hydrogen peroxide scavenging activity - HPSA, ferric reducing antioxidant power - FRAP, and ferrous ion chelating activity - FICA), element concentrations and antimicrobial activity. Main results: According to the melissopalynological analysis, one sample was determined to be unifloral and nine samples were found to be multifloral. The values found ranged 271.42-601.85 mg GAE/100 g TPC, 23.53-34.50 mg CAE/100 g TFC, 22.19-23.78 μg/mL DPPH, 6.50-78.40 µg/mL ABTS, 20.43-150.94 μg/mL HPSA, 97.26-99.83% FRAP and 74.84-91.79% FICA. Rosmanic acid, p-coumaric acid, quercetin, apigenin, and naringin were identified in all samples, while catechin was detected only in S6 and S7. Element contents were found Mg &gt; Fe &gt; Mn &gt; Zn &gt; Cu &gt; Se &gt; Cr &gt; Ni &gt; Cd &gt; Co. All the samples had high antibacterial activity against Bacillus cereus (MIC= 4.17-8.33 g/mL), and against Staphylococcus aureus (MIC= 8.33 g/mL), except S3 and S4. Research highlights: Different levels and combinations of these components are efficient in the antioxidant and antibacterial activity of pollen.